SOLUTION: If f(x) varies directly with x^2, and f(x) = 75 when x = 5, find the value of f(4).
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Question 841441: If f(x) varies directly with x^2, and f(x) = 75 when x = 5, find the value of f(4).
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
 = kx^2)
for some constant k
 = 25k = 75 \Rightarrow k = 3)
Therefore  = 3 \cdot 4^2 = 48)
.
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